The invention relates to a modular construction system, for instance for educational purposes or for use as toy, which system comprises at least two profile parts for mutual releasable coupling by means of a coupling part, wherein the coupling part is provided on at least two different sides thereof with one or more radially protruding lips and a recessed portion present behind the lips as seen in coupling direction, and wherein each profile part is provided in at least one wall thereof with a continuous opening with different dimensions as seen in at least two different radial directions, wherein the larger dimension is larger than or equal to the maximum radial section through the lips and wherein the smaller dimension is smaller than said radial section, wherein the wall thickness at the position of the opening is smaller than or equal to the width of the recessed portion on the coupling part, this such that coupling takes place by receiving of the lips in the opening and by subsequent radial rotation of the coupling part and each profile part relative to each other.
In the modular construction system according to the invention the components can only be pushed into each other at particular mutual orientations and then be coupled by means of rotation. By playing with this toy the spatial awareness of children can be developed at a young age. By adapting for instance the number of lips or the complexity of the shape of the opening in combination with the size, the toy can be made suitable for children in most age groups. The described rotating coupling can in addition withstand relatively high loads, which provides the option of giving components of the modular construction system a heavier and therefore larger form. By giving for instance the profile parts a relatively large form, it is possible to obtain a comparatively large construction volume within a short time by mutually coupling a number of these profile parts. Particularly in the use as toy, this will have a highly motivating effect on a child. It is noted moreover that to the best of applicant""s knowledge this aspect is not provided for by other toys. The thus embodied profile parts and coupling parts can furthermore be manufactured especially well using known injection moulding techniques.
In a first preferred embodiment the coupling part is provided with two or more lips on each of the at least two different sides. In a second preferred embodiment there are four lips.
In a further preferred embodiment the coupling part comprises at least two sets of one or more lips fixed to a central part, wherein the recessed portion associated with each set of lips is bounded by the lips and the central part. In order to bring about a precise mutual connection of the profile parts and coupling parts, the transverse shape of the central part is preferably substantially the same as the transverse shape of the profile part. In a further development of this preferred embodiment, each profile part comprises in the wall provided with the opening a recess for receiving at least a portion of the central part. In the coupled situation of two profile parts the relevant coupling part is in this way concealed from view. In order to facilitate handling, grooves running parallel to the coupling direction can be arranged on the central part, for instance for co-action with a tool. In another preferred embodiment the central part is embodied substantially in the shape of a cube. A set of one or more lips can herein be arranged on all six sides of the cube-shaped central part. Such a coupling part enables the construction of many structures, also more complicated ones. In another preferred embodiment the form and dimensions of at least one of the walls of each profile part provided with the opening are the same as the form and dimensions of the walls of the cube-shaped central part. In this embodiment the cube-shaped coupling part defines as it were a basic unit or basic module. By choosing the dimensions of the profile parts for instance such that these correspond with a whole number of times the dimensions of the basic module, larger units can for instance be constructed with a shape analogous to the basic module.
The coupling part is preferably embodied mirror-symmetrically as seen in transverse direction. This has the advantage among others that the coupling part is simpler to manufacture. In addition, the mirror-symmetrical embodiment provides the option of constructing generally mirror-symmetrical structures.
In yet another preferred embodiment, the sets of lips are mounted rotatably on the central part. Using a specific tool, which can for instance be placed through another opening on the profile part, the lips can then be rotated into the desired position.
In the simplest form the opening is square. In a more complex form, the shape of the part of the coupling part which is provided with the lips and which co-acts with the opening, is substantially complementary to the shape of the opening. In order to obtain a better clamping, the wall in a further preferred embodiment increases at least partially in thickness as seen in the rotation direction at the position of the opening.
A positioning edge is preferably arranged on at least one part of the peripheral edge of the opening.
In a following preferred embodiment means are provided for locking the components against further radial rotation. The means preferably comprise co-acting cams and recesses, which cams respectively recesses are arranged on the rear of the lips as seen in coupling direction and the recesses respectively cams co-acting therewith are arranged on the inside of the profile part adjacently of the opening at the position of the smaller dimension thereof.
In yet another preferred embodiment the material comprises plastic, preferably ABS (ABS=acrylonitrile-butadiene-styrene), ASA (ASA=acrylonitrile-styrene-acrylester-rubber) or a combination of ABS and PA (PA=polyamide). ABS and ASA have a good scratch-resistance and a great stiffness. ABS in particular has very good optical qualities, which provides the option of supplying the modular construction system in many different colors, wherein the color-fastness is ensured. ABS has the advantage compared to ASA that it is less expensive. The combination of ABS and PA has high color-fastness as well as a high degree of insusceptibility to wear.